Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Quantos voluntários dos EUA participaram de cada programa em 2021?
 ###Tabelas: 
CREATE TABLE Volunteers (VolunteerID INT, VolunteerName TEXT, Country TEXT); INSERT INTO Volunteers (VolunteerID, VolunteerName, Country) VALUES (1, 'Alice', 'USA'); INSERT INTO Volunteers (VolunteerID, VolunteerName, Country) VALUES (2, 'Bob', 'Mexico'); CREATE TABLE VolunteerPrograms (ProgramID INT, ProgramName TEXT); INSERT INTO VolunteerPrograms (ProgramID, ProgramName) VALUES (1, 'Feeding the Homeless'); INSERT INTO VolunteerPrograms (ProgramID, ProgramName) VALUES (2, 'Tutoring Kids'); CREATE TABLE VolunteerEvents (EventID INT, ProgramID INT, VolunteerID INT, EventDate DATE); INSERT INTO VolunteerEvents (EventID, ProgramID, VolunteerID, EventDate) VALUES (1, 1, 1, '2021-01-01'); INSERT INTO VolunteerEvents (EventID, ProgramID, VolunteerID, EventDate) VALUES (2, 2, 2, '2021-02-01');
SELECT VolunteerPrograms.ProgramName, COUNT(DISTINCT Volunteers.VolunteerID) AS VolunteerCount FROM Volunteers INNER JOIN VolunteerEvents ON Volunteers.VolunteerID = VolunteerEvents.VolunteerID INNER JOIN VolunteerPrograms ON VolunteerEvents.ProgramID = VolunteerPrograms.ProgramID WHERE Volunteers.Country = 'USA' AND YEAR(VolunteerEvents.EventDate) = 2021 GROUP BY VolunteerPrograms.ProgramName;